Brief Answer:
Get yourself clinically examined and investigated.

Detailed Answer:
Hi,
Thanks for writing your query.

After reading your post, I would like to advise that you should get yourself clinically examined and investigated to know the cause of your low hemoglobin.
It can be a possibility that there is some microscopic blood loss which is not visible by naked eyes. It is common in Urinary Tract Infection ( UTI ) or bleeding gastric ulcers.

I would suggest that you should go for following investigations :-
1. Urine examination.
2. Stool examination for occult blood.
3. Endoscopy if stool examination is positive for occult blood.

I would also suggest a clinical examination for any hemorrhoids. Other common cause in females can be excessive menstrual bleeding.

You can take foods rich in iron like pomegranate, jaggery, green leafy vegetables.

Low hemoglobin can result in fatigue and swelling of the body which can appear as weight gain.
If you are gaining weight, you can go for weight management exercises and diet control. You will not feel fatigued once the hemoglobin improves.

Further medical management can be planned after clinical evaluation and knowing the reports of the investigations.

I hope this is helpful to you.
If you have any further query, I will be happy to help.
Thanks.

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